Static electric field therapy by high voltage alternating current (EF-HVAC) is a traditional complementary Japanese medicine used for headache, shoulder stiffness, chronic constipation and insomnia. Open-label studies and clinical experience in Japan have suggested that this electric field therapy is safe and effective in treating chronic arthritis. We evaluated the efficacy of EF-HVAC therapy ...

Control of energy flows within a building is critical to achieving optimal performance of heating, ventilation and air-conditioning (HVAC) systems. To design optimal HVAC control strategies, a dynamic model of the HVAC system – particularly the building zones that it services – is essential. As analysis of building energy consumption is facilitated by the accurate prediction of indoor environme...

Paper presents role of fuzzy modeling in heating, ventilating and air conditioning (HVAC) and control models. HVAC design professionals are required to evaluate numerous design alternatives and properly justify their final conceptual selection through modeling. This trend, coupled with the knowledge of experienced designers, increasing complexity of the systems, unwillingness to commit addition...

Nearly 20% of total energy consumption in the United States is accounted for in heating, ventilation, and air conditioning (HVAC) systems. Smart sensing and adaptive energy management agents can greatly decrease the energy usage of HVAC systems in many building applications, for example by enabling the operator to shut off HVAC to unoccupied rooms. We implement a multi-modal sensor agent that i...

Conventional heating, ventilating, and air conditioning (HVAC) systems have traditionally used the temperature and the humidity ratio as the quantitative indices of comfort in a room. Recently, the carbon dioxide (CO2) concentration has also been recognized as having an important contribution to room comfort. This paper presents the modeling of an augmented HVAC system including CO2 concentrati...

Failures can lead to a series of problems in the complex heating, ventilation and air-conditioning (HVAC) systems in buildings. Fault detection and diagnosis (FDD) is an important technology to solve these problems. Models can represent the behaviors of the HVAC systems, and FDD can be realized with models. Using the model as intermediary, a link between system simulation and FDD can be built. ...

HVAC systems constitute ∼ 40% of energy in commercial buildings, and faults in HVAC account for 5% to 20% of its energy consumption. Typically, HVAC in modern buildings are managed using Building Managing Systems (BMS), and fault detection is one of the essential services provided by BMS to keep HVAC operational. We study the fault management practices followed in real commercial buildings, and...

Control methodologies could achieve better comfort conditions of heating, ventilating and air conditioning (HVAC) systems, however, the application of classical controllers is unsatisfactory as HVAC systems are non-linear and the control variables such as temperature and relative humidity (RH) inside the thermal zone are coupled. The objective of this study is to implement and simulate adaptive...

In this paper, the mathematical model of a HVAC (Heating, Ventilation and Air-Conditioning) equipment is described. This system is inserted into a computer code developed in Matlab/Simulink platform which is devoted to the analysis of building thermal behavior and HVAC closed-loop control performance. The model is presented in terms of non-linear state-space equations that represent the energy ...

Researchers have extensively explored predictive control strategies for controlling heating, ventilation, and air conditioning (HVAC) units in commercial buildings. Predictive control strategies, however, critically rely on weather and occupancy forecasts. Existing state-of-the-art building simulators are incapable of analysing the in uence of prediction errors (in weather and occupancy) on HVA...